Electronic pen

ABSTRACT

A work step of electrical connection between a writing pressure detector and a circuit element of a circuit is reduced. An electronic pen includes a writing pressure detector that detects a pressure applied to a core body disposed on one end side of a tubular chassis in the axial center direction, a circuit board for which a flexible substrate formed into a shape allowed to extend in the axial center direction is used in the chassis, and a holder housed in the chassis in such a manner as to hold the writing pressure detector and the circuit board and extend in the axial center direction. In the circuit board, a writing pressure detector placement part, a circuit placement part at which a predetermined circuit is formed, and a line part at which a line pattern that electrically connects a component of the writing pressure detector placed on the writing pressure detector placement part and a circuit element of the circuit placement part is formed are formed to line up in the axial center direction. The writing pressure detector placement part of the circuit board is held by the holder in the state of being along a direction perpendicular to the axial center direction in such a manner that the writing pressure detector can receive a pressure in the axial center direction applied to the core body through bending of the flexible substrate at a part of the line part.

BACKGROUND Technical Field

This disclosure relates to an electronic pen that is used with aposition detecting device and has a writing pressure detection functionfor detecting a pressure (writing pressure) applied to a core body.

Description of the Related Art

Conventionally, the electronic pen is configured to have a function fordetecting a pressure (writing pressure) applied to the tip part (pentip) of a core body and transmitting the pressure to a positiondetecting device. In this case, a configuration of a writing pressuredetecting unit using a mechanism that changes the capacitance of acapacitor according to the writing pressure as one example of a methodfor detecting the writing pressure is known (for example, refer toPatent Document 1 (Japanese Patent Laid-open No. 2011-186803)).

The writing pressure detecting unit described in this Patent Document 1includes a dielectric and a first electrode and a second electrode thatsandwich the dielectric and are opposed to each other, and is configuredin such a manner that the contact area between one electrode of the twoelectrodes, for example, the first electrode, and the dielectric changesdepending on the pressure applied to the core body. According to thisconfiguration, the capacitance between the first electrode and thesecond electrode changes according to the contact area between the firstelectrode part and the dielectric, which changes according to thepressure applied to the core body. Therefore, the writing pressure canbe detected by detecting the capacitance.

Conventionally, this writing pressure detecting unit is manufactured byinserting and disposing all of the plurality of components into a hollowpart of a tubular holder from openings on one side and the other side inthe axial center direction of this holder. For this reason, all of theplurality of components configuring the writing pressure detecting unitneed to be inserted and disposed into the hollow part of the holder withconsideration of position alignment in the axial center direction and inthe direction orthogonal to the axial center direction regarding all ofthe plurality of components configuring the writing pressure detectingunit. However, there is a problem that it is difficult to carry out theposition alignment in the axial center direction and in the directionorthogonal to the axial center direction. For this reason, there is aproblem in that it is difficult and takes increased man-hours tomanufacture the writing pressure detecting unit, making the writingpressure detecting unit unsuitable for mass production.

For example, an electronic pen in which this program is resolved isprovided in Patent Document 2 (Japanese Patent Laid-open No.2014-206775). In the electronic pen disclosed in this Patent Document 2,a printed board on which circuit elements for a writing pressuredetecting circuit for detecting a pressing force applied to the tip of acore body are disposed is placed on a printed board placement part andis locked. In addition, the electronic pen includes a holder unitincluding a holding part for holding components for writing pressuredetection. Furthermore, the holding part of the holder unit is formedinto a tubular shape. In addition, the holding part has an openingoriented in a direction orthogonal to the axial center direction and hasa configuration in which at least part of the components for writingpressure detection is inserted from the opening. The electronic pen ofPatent Document 2 with this configuration can alleviate difficulty inwork in the step of manufacturing the writing pressure detector andprovides an effect of being suitable for mass production.

PRIOR ART DOCUMENT Patent Documents

Patent Document 1: Japanese Patent Laid-open No. 2011-186803

Patent Document 2: Japanese Patent Laid-open No. 2014-206775

BRIEF SUMMARY Technical Problems

However, also in the electronic pen of Patent Document 2, the firstelectrode and the second electrode of the writing pressure detectingunit and the circuit elements for the writing pressure detecting circuitof the printed board are electrically connected by soldering, forexample, and this electrical connection is necessary as another step.

In view of the above points, the present disclosure provides anelectronic pen that reduces manufacturing steps, including an electricalconnection between a writing pressure detector and a writing pressuredetecting circuit.

Technical Solution

At least one embodiment of the present disclosure is directed to anelectronic pen including:

a tubular chassis;

a core body disposed on an end side of the tubular chassis in an axialcenter direction;

a writing pressure detector configured to detect a pressure applied tothe core body;

a circuit board including a flexible substrate and a longitudinal lengthextending in the axial center direction, wherein the circuit board is inthe tubular chassis, the circuit board comprising:

-   -   a writing pressure detector placement part, at least a portion        of the writing pressure detector located on and coupled to the        writing pressure detector part;    -   a circuit placement part, a predetermined circuit formed on the        flexible substrate at the circuit placement part; and    -   a line part arranged between the writing pressure detector        placement part and the circuit placement part in the axial        center direction, a conductive line pattern formed at the line        part that electrically couples the writing pressure detector and        the circuit of the circuit placement part; and

a holder housed in the tubular chassis in such a manner as to hold thewriting pressure detector and the circuit board and extend in the axialcenter direction,

wherein the circuit placement part of the circuit board is held by theholder, and wherein the writing pressure detector placement part of thecircuit board is configured in such a manner that, through bending ofthe flexible substrate at a part of the line part, the writing pressuredetector placement part is held by the holder in a directionperpendicular to the axial center direction, and the writing pressuredetector is allowed to receive a pressure in the axial center directionapplied to the core body.

In the electronic pen with the above-described configuration, theflexible substrate is used for the circuit board. In addition, thecircuit board includes the circuit placement part at which thepredetermined circuit including a writing pressure detecting circuit,for example, is formed, the writing pressure detector placement partonto which at least part of components of the writing pressure detectoris placed and fixed, and the line part at which the line pattern thatelectrically connects the circuit placement part and the writingpressure detector placement part is formed. Therefore, the state isobtained in which the electrical connection between the component placedand fixed onto the writing pressure detector placement part in thewriting pressure detector and the circuit element of the circuitplacement part is made on the circuit board in advance. For this reason,a work step of the electrical connection between the component placedand fixed onto the writing pressure detector placement part in thewriting pressure detector and the circuit element of the circuitplacement part becomes unnecessary.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

FIGS. 1A and 1B depict diagrams for explaining one example of a firstembodiment of an electronic pen according to the present disclosure.

FIGS. 2A and 2B depict diagrams for explaining one example of anelectronic pen main body of the first embodiment of the electronic penaccording to the present disclosure.

FIGS. 3A-3C depict partially enlarged views of the one example of theelectronic pen main body of the first embodiment of the electronic penaccording to the present disclosure.

FIG. 4 is an exploded perspective view of part of the one example of theelectronic pen main body of the first embodiment of the electronic penaccording to the present disclosure.

FIGS. 5A-5E depict diagrams for explaining an example of a circuit boardand a holder unit in the one example of the electronic pen main body ofthe first embodiment of the electronic pen according to the presentdisclosure.

FIGS. 6A and 6B depict diagrams for explaining an example of a writingpressure detector in the one example of the electronic pen main body ofthe first embodiment of the electronic pen according to the presentdisclosure.

FIG. 7 is a diagram for explaining the one example of the electronic penmain body of the first embodiment of the electronic pen according to thepresent disclosure.

FIG. 8 is a diagram for explaining an example of an electronic circuitof the first embodiment of the electronic pen according to the presentdisclosure and an electronic circuit example of a corresponding positiondetecting device.

FIGS. 9A-9D depict diagrams for explaining an example of a circuit boardand a holder unit in one example of an electronic pen main body of asecond embodiment of the electronic pen according to the presentdisclosure.

FIGS. 10A-10C depict partially enlarged views of the one example of theelectronic pen main body of the second embodiment of the electronic penaccording to the present disclosure.

FIGS. 11A-11C depict partially enlarged views of another example of theelectronic pen main body of the second embodiment of the electronic penaccording to the present disclosure.

FIGS. 12A and 12B depict partially enlarged views of one example of anelectronic pen main body of a third embodiment of the electronic penaccording to the present disclosure.

FIG. 13 is a circuit diagram illustrating an electronic circuit exampleof a fourth embodiment of the electronic pen according to the presentdisclosure.

DETAILED DESCRIPTION

Several embodiments of the electronic pan according to this disclosurewill be described below with reference to the drawings.

First Embodiment

FIGS. 1A and 1B depict diagrams illustrating a configuration example ofa first embodiment of the electronic pen according to this disclosureand this example is the case of an electronic pen of the electromagneticinduction system. An electronic pen 1 of this first embodiment has aknock-type configuration in which an electronic pen main body 3 ishoused in a hollow part 2 a of a tubular chassis 2 and the pen tip sideof the electronic pen main body 3 is protruded and retracted from theside of an opening 2 b at one end of the chassis 2 in the longitudinaldirection by a knock cam mechanism 10. In this embodiment, theelectronic pen main body 3 has a cartridge-type configuration and isallowed to be attached and detached to and from the chassis 2.

FIG. 1A illustrates the state in which the whole of the electronic penmain body 3 is housed in the hollow part 2 a of the chassis 2. FIG. 1Billustrates the state in which the pen tip side of the electronic penmain body 3 protrudes from the opening 2 b of the chassis 2 by the knockcam mechanism 10. The example of FIGS. 1A and 1B are illustrated as thestate in which the chassis 2 of the electronic pen 1 is composed of atransparent synthetic resin and the inside thereof is see-through.

The electronic pen 1 of this embodiment is configured to ensurecompatibility with a commercially-available knock-type ballpoint pen.

The chassis 2 and the knock cam mechanism 10 disposed in this chassis 2have the same configuration as a well-known commercially-availableknock-type ballpoint pen and are configured identically also regardingthe dimensional relation. In other words, it is also possible to use thechassis and the knock cam mechanism of the commercially-availableknock-type ballpoint pen as they are as the chassis 2 and the knock cammechanism 10.

As illustrated in FIGS. 1A and 1B, the knock cam mechanism 10 has awell-known configuration in which a cam main body 11, a knock bar 12,and a rotary element 13 are combined. The cam main body 11 is formed onthe inner wall surface of the tubular chassis 2. An end part 12 a of theknock bar 12 is made to protrude from an opening 2 c of the chassis 2 onthe opposite side to the pen tip side such that knock operation by auser can be accepted. The rotary element 13 has a fitting part 13 a towhich the end part of the electronic pen main body 3 on the oppositeside to the pen tip side is fitted.

When the end part 12 a of the knock bar 12 is pressed down in the stateof FIG. 1A, the electronic pen main body 3 is locked into the state ofFIG. 1B in the chassis 2 by the knock cam mechanism 10, which providesthe state in which the pen tip side of the electronic pen main body 3protrudes from the opening 2 b of the chassis 2. Then, when the end part12 a of the knock bar 12 is pressed down again from this state of FIG.1B, the locked state is released by the knock cam mechanism 10 and theposition of the electronic pen main body 3 in the chassis 2 returns tothe state of FIG. 1A by a return spring 5. The detailed configuration ofthe knock cam mechanism 10 and the operation thereof are well known andtherefore description thereof is omitted here.

Embodiment of Electronic Pen Main Body 3

FIGS. 2A and 2B depict diagrams illustrating a configuration example ofthe electronic pen main body 3 with comparison with a refill of acommercially-available knock-type ballpoint pen. Specifically, FIG. 2Aillustrates a refill 6 of the commercially-available knock-typeballpoint pen and FIG. 2B illustrates the configuration example of theelectronic pen main body 3 of this embodiment.

As illustrated in FIG. 2A, the refill 6 of the commercially-availableknock-type ballpoint pen has a well-known configuration in which a pentip part 6 a in which a ball is disposed at the tip and an ink storage 6c are joined at a joint part 6 b and are integrated. The joint part 6 bhas the same diameter as the ink storage 6 c.

On the other hand, as illustrated in FIG. 2B, the electronic pen mainbody 3 of this embodiment is composed of a core body 30, a signaltransmitter 40, a holder 50 that holds a writing pressure detector andholds a circuit board as described later, a cartridge chassis component60 having a function of housing and protecting the writing pressuredetector and the circuit board held by the holder 50, and a rear endcomponent 70 disposed to be joined to the cartridge chassis component 60on the opposite side to the core body side.

The core body 30 is a bar-shaped component composed of a resin materialthat is comparatively hard and has elasticity in this example, forexample, polyoxymethylene (POM), and the diameter thereof is set toapproximately 1 mm, for example.

The signal transmitter 40 is composed of a coil 41 forming a resonantcircuit for transmitting and receiving a signal with a positiondetecting device by the electromagnetic induction system, a magneticcore around which this coil 41 is wound, a ferrite core 42 in thisexample, and a core pipe member 43 fitted and fixed into a penetrationhole 42 a of this ferrite core 42.

The holder 50 is composed of a resin material, for example, and holdsthe writing pressure detector. In addition, the holder 50 includes atubular part 51 fitted to the ferrite core 42 of the signal transmitter40 and includes a circuit board placement base part 52 (see FIG. 4 to bedescribed later), for which diagrammatic representation is omitted inFIGS. 2A and 2B.

The cartridge chassis component 60 is formed of a component that iscomposed of a hard material and has a pipe shape, a component that iscomposed of a metal and has a pipe shape in this example, and forms acircuit part protecting component that protects an electrical circuitconfiguring part of the writing pressure detector and the circuit board.

The opposite side to the pen tip side in the axial center direction inthe ferrite core 42 and the core pipe member 43 of the signaltransmitter 40 is inserted and fitted into the tubular part 51 of theholder 50 and the signal transmitter 40 and the holder 50 are joined inthe axial center direction. Furthermore, the cartridge chassis component60 and the holder 50 are joined in the axial center direction in thestate in which the circuit board placement base part 52 and part of thetubular part 51 in the holder 50 are housed in a hollow part of thecartridge chassis component 60. Moreover, in the axial center direction,the rear end component 70 is joined to the opposite side to the sidejoined to the signal transmitter 40 in the cartridge chassis component60. Through the joining of the signal transmitter 40, the holder 50, thecartridge chassis component 60, and the rear end component 70 in theaxial center direction in the above-described manner, the electronic penmain body 3 is caused to have a configuration of a cartridge setidentical to the refill 6 of a ballpoint pen as the outer shape.

In the rear end component 70, two bar-shaped members 71 and 72 dividedin the axial center direction are joined to each other with theintermediary of a joining bar 73 in the state that the bar-shapedmembers 71 and 72 can move in such a manner as to come closer to eachother in the axial center direction. Furthermore, a coil spring 74 isdisposed between the two bar-shaped members 71 and 72 in such a manneras to house the joining bar 73 in the winding space thereof. Normallythe two bar-shaped members 71 and 72 are elastically displaced to beseparated from each other by this coil spring 74. The configuring partincluding the coil spring 74 in this rear end component 70 is a partthat plays a role of a shock absorber (shock absorbing component) thatabsorbs a shock load (shock pressure) and protects the electronic penmain body 3 when the shock load is applied to the side of the core body30 of the electronic pen main body 3. That is, when the shock load isapplied in the axial center direction of the electronic pen main body 3,the coil spring 74 contracts corresponding to the shock load and worksto absorb the shock. If the shock load disappears, the bar-shapedmembers 71 and 72 return to the original separated state due to the coilspring 74 of the rear end component 70.

FIG. 3A is a diagram illustrating the whole of the signal transmitter 40and the joining part of this signal transmitter 40, the holder 50, andthe cartridge chassis component 60 in an enlarged manner. Furthermore,FIG. 3B is a longitudinal sectional view of FIG. 3A. However, in FIG.3B, the core pipe member 43 and the core body 30 are illustrated withoutbeing broken for convenience of explanation.

As the ferrite core 42 of this example, what is obtained by forming thepenetration hole 42 a (see FIG. 3B) in the axial center direction with apredetermined diameter for insertion of the core pipe member 43 in aferrite material with a circular column shape, for example, is employed.A taper part 42 b gradually tapered is formed on the pen tip side ofthis ferrite core 42. Due to this taper part 42 b, the density ofmagnetic flux that passes through this ferrite core 42 becomes highdensity at the taper part 42 b, and magnetic coupling with a sensor ofthe position detecting device can be made stronger compared with thecase in which the taper part 42 b does not exist.

Furthermore, in this embodiment, as illustrated in FIG. 3A, the coil 41is not wound across the whole length of the ferrite core 42 in the axialcenter direction but wound partly. Specifically, in this example, thecoil 41 is set to have the winding length approximately half the wholelength of the ferrite core 42. In addition, as illustrated in FIG. 3A,the wound part of this coil 41 around the ferrite core 42 is set at aposition biased to the part joined to the tubular part 51 of the holder50 in the ferrite core 42.

Moreover, when the ferrite core 42 is viewed in the axial centerdirection thereof, the part from the end part thereof on the pen tipside to one end of the wound part of the coil 41 is set as a firstnon-coil-wound part 42 c around which the coil 41 is not wound.Furthermore, the slight part from the other end of the wound part of thecoil 41 to the side of the part joined to the tubular part 51 of theholder 50 is also set as a second non-coil-wound part 42 d around whichthe coil 41 is not wound. The length of the second non-coil-wound part42 d in the axial center direction is set to a short length for joiningto the tubular part 51 of the holder 50 (see FIG. 3B). On the otherhand, in this example, the length of the first non-coil-wound part 42 cin the axial center direction is set to a comparatively-long lengthobtained by subtracting the length of the second non-coil-wound part 42d from the length approximately half the whole length of the ferritecore 42.

The core pipe member 43 is formed of a metal in this example. Asillustrated in FIG. 3B, the core pipe member 43 has an outer diameterslightly smaller than the diameter of the penetration hole 42 a of theferrite core 42. The core pipe member 43 is inserted in the penetrationhole 42 a of the ferrite core 42 and is attached through being joinedand fixed to the ferrite core 42 by an adhesive, for example.

As illustrated in FIG. 3B, the core pipe member 43 is set longer thanthe length of the ferrite core 42 in the axial center direction. Thus,the core pipe member 43 includes protruding parts 43 a and 43 b thatprotrude to the pen tip side and the opposite side to the pen tip siderelative to the penetration hole 42 a of the ferrite core 42. In thisexample, as illustrated in FIG. 3B, the protruding part 43 b of the corepipe member 43 on the opposite side to the pen tip side is set to havean outer diameter larger than the diameter of the penetration hole 42 aof the ferrite core 42. By this protruding part 43 b, the core pipemember 43 is kept from dropping off from the penetration hole 42 a ofthe ferrite core 42 to the pen tip side.

Furthermore, the diameter of a penetration hole 43 c (see dotted linepart of the core pipe member 43 in FIG. 3B) of the core pipe member 43is set slightly larger than the diameter of the core body 30, and thecore body 30 is configured to be capable of being inserted movably inthe axial center direction in this penetration hole 43 c of the corepipe member 43. The length of the core body 30 is selected to be longerthan the length of the core pipe member 43 as illustrated in FIG. 3C. Inthe case of this example, the length of the core body 30 is set to alength with which, as illustrated in FIG. 3B, one end part 30 a(hereinafter, referred to as pen tip part 30 a) of the core body 30 canprotrude from the pen tip side of the ferrite core 42 and the core pipemember 43 as the pen tip and protrusion also to the opposite side to thepen tip side, of the ferrite core 42 and the core pipe member 43, ispossible. The core pipe member 43 has functions of reinforcing theferrite core 42 having the penetration hole 42 a and protecting the corebody 30 that protrudes to the pen tip side of the ferrite core 42 and isthin by the protruding part 43 a protruding relative to the pen tip sideof the ferrite core 42 such that the core body 30 may be kept from beingbroken.

Furthermore, as illustrated in FIG. 3B, the tubular part 51 of theholder 50 has a fitting recess 51 a with almost the same diameter as thediameter of the second non-coil-wound part 42 d of the ferrite core 42,a housing part 51 b having a housing space in which a writing pressuredetector 80 to be described in detail later is housed, and a penetrationhole 51 c that penetrates between the fitting recess 51 a and thehousing part 51 b and has an inner diameter almost the same as the outerdiameter of the protruding part 43 b of the core pipe member 43 on theopposite side to the pen tip side.

Moreover, the ferrite core 42 is joined to the tubular part 51 of theholder 50 in the state in which the second non-coil-wound part 42 d ofthe ferrite core 42 of the signal transmitter 40 is fitted into thefitting recess 51 a and the protruding part 43 b of the core pipe member43 on the opposite side to the pen tip side is fitted into thepenetration hole 51 c. At this time, as illustrated in FIG. 3B, apressure transmitting component 31 and a coil spring 32 illustrated inFIGS. 3B and 3C are disposed in the penetration hole 51 c of the tubularpart 51 prior to the joining to the ferrite core 42 and the core pipemember 43.

The pressure transmitting component 31 is a component for transmittingthe pressure (writing pressure) applied to the pen tip part 30 a of thecore body 30 to a pressure receiving part of the writing pressuredetector 80 and is formed of a component having elasticity, a resinhaving elasticity in this example. As illustrated in FIGS. 3B and 3C,the pressure transmitting component 31 of this example includes apressing tip part 31 a with a diameter slightly smaller than thediameter of the penetration hole 51 c of the tubular part 51 and acolumnar part 31 b with a diameter smaller than the inner diameter ofthe coil spring 32. Furthermore, in the columnar part 31 b, a fittingrecess 31 c (see dotted line part of the pressure transmitting component31 in FIGS. 3B and 3C) into which an end part 30 b of the core body 30on the opposite side to the pen tip part 30 a is fitted and locked isformed.

The length of the coil spring 32 in the axial center direction isselected to be slightly longer than the length of the columnar part 31 bof the pressure transmitting component 31 in the axial center direction.Because the diameter of the columnar part 31 b of the pressuretransmitting component 31 is smaller than the inner diameter of the coilspring 32, the coil spring 32 becomes the state in which it is disposedaround the columnar part 31 b as illustrated in FIG. 3B.

Furthermore, in the state in which the ferrite core 42 and the core pipemember 43 of the signal transmitter 40 are fitted into the tubular part51 of the holder 50, the coil spring 32 exists between the tip of theprotruding part 43 b of the core pipe member 43 on the opposite side tothe pen tip side and the pressure receiving part of the writing pressuredetector 80 in the penetration hole 51 c of the tubular part 51 asillustrated in FIG. 3B. Therefore, due to elasticity of this coil spring32, the pressure transmitting component 31 is set to the state in whichit always abuts against the pressure receiving part of the writingpressure detector 80.

Moreover, after the ferrite core 42 and the core pipe member 43 of thesignal transmitter 40 are fitted into the tubular part 51 of the holder50, the core body 30 is caused to penetrate through the penetration hole43 c of the core pipe member 43 and the end part 30 b thereof is fittedinto the fitting recess 31 c of the pressure transmitting component 31.The core body 30 can be released from the fitting to the pressuretransmitting component 31 and be withdrawn by pulling the pen tip part30 a. Therefore, the core body 30 can be replaced.

When a space exists between the tip of the pressing tip part 31 a of thepressure transmitting component 31 and the pressure receiving part ofthe writing pressure detector 80, in carrying out operation of pressingthe electronic pen 1 against an input surface of the position detectingdevice to attempt writing, the pen tip part 30 a retreats correspondingto the space although a writing pressure is not applied, and a sense ofdiscomfort is given to the user. In contrast, in this embodiment, thepressure transmitting component 31 is set to the state in which italways abuts against the pressure receiving part of the writing pressuredetector 80 due to elasticity of the coil spring 32, and the space iskept from being generated. For this reason, in carrying out operation ofpressing the electronic pen 1 against the input surface of the positiondetecting device to attempt writing, the problem that the pen tip part30 a retreats corresponding to the space does not occur. Due to this,the writing pressure can be detected at the moment when the pen tip part30 a gets contact with the input surface of the sensor of the positiondetecting device, which provides the optimum feeling of writing forentry of characters.

In the electronic pen of this embodiment, as illustrated in FIG. 1B,when the pen tip part 30 a of the core body 30 protrudes from theopening 2 b of the chassis 2 of the electronic pen 1, part of the pentip side of the first non-coil-wound part 42 c of the ferrite core 42and the protruding part 43 a of the core pipe member 43 on the pen tipside also become the state of protruding from the opening 2 b of thechassis 2.

Next, parts of the holder 50, the writing pressure detector 80 and acircuit board 90 held by this holder 50, and the cartridge chassiscomponent 60 will be described by using FIGS. 4 to 7.

FIG. 4 is an exploded perspective view illustrating the holder 50, thewriting pressure detector 80 and the circuit board 90 held by thisholder 50, and the cartridge chassis component 60 in a disassembledmanner.

The holder 50 is a boat-shaped component that is elongated in the axialcenter direction and includes the above-described tubular part 51 on thepen tip side, and is composed of an insulating material, a resin in thisexample. In this holder 50, the circuit board placement base part 52 onwhich the circuit board 90 is placed is set monolithically with thetubular part 51. The circuit board placement base part 52 includes aflat surface part 52 a obtained by cutting a circular column along a cutplane including the center line thereof. That is, the circuit boardplacement base part 52 is formed into a columnar shape whose section isa semicircle in this example.

Furthermore, the longitudinal direction of the flat surface part 52 a ofthe circuit board placement base part 52 is the axial center directionof the tubular part 51 and the length (width) thereof in the short-sidedirection is set slightly shorter than the inner diameter of thecartridge chassis component 60. Therefore, the circuit board placementbase part 52 is configured to be housed in the cartridge chassiscomponent 60.

The outer diameter of the tubular part 51 of the holder 50 is setidentical to the outer diameter of the cartridge chassis component 60 onthe pen tip side, and the tubular part 51 is set to have the same outerdiameter as the width of the flat surface part 52 a of the circuit boardplacement base part 52 on the side of the circuit board placement basepart 52. Thus, a step part 51 d is formed at the position of theboundary between the parts different in the outer diameter. Therefore,when the holder 50 is inserted in the cartridge chassis component 60,the end surface of the cartridge chassis component 60 on the pen tipside abuts against the step part 51 d and the holder 50 and thecartridge chassis component 60 are joined in the state. That is, in thecartridge chassis component 60, the circuit board placement base part 52of the holder 50 and the part to the step part 51 d on the side of thecircuit board placement base part 52 in the tubular part 51 are housed.The outer diameter of the part on the pen tip side relative to the steppart 51 d in the tubular part 51 of the holder 50 is the same as theouter diameter of the cartridge chassis component 60. Therefore, in thestate in which the holder 50 and the cartridge chassis component 60 arejoined, the step part 51 d disappears in appearance and the holder 50and the cartridge chassis component 60 become one bar-shaped body.

FIG. 5A is a diagram of the holder 50 when the flat surface part 52 a ofthe circuit board placement base part 52 is viewed from directly above.Furthermore, FIG. 5B is a diagram when the holder 50 is viewed from theopposite side to the side of the flat surface part 52 a of the circuitboard placement base part 52.

As illustrated in FIG. 4 and FIG. 5A, the housing part 51 b of theabove-described writing pressure detector 80 is set at the part on theside of the circuit board placement base part 52 relative to the steppart 51 d in the tubular part 51 of the holder 50. The part on the sideof the circuit board placement base part 52 relative to the step part 51d corresponding to the part of this housing part 51 b is set as anopening part 51 bm oriented in a direction orthogonal to the axialcenter direction, and the configuration is made in such a manner thatthe writing pressure detector 80 can be inserted into the housing part51 b from the direction orthogonal to the axial center direction throughthis opening part 51 bm.

Furthermore, as illustrated in FIG. 4 and FIG. 5A, a wall part 51 ehaving a wall surface orthogonal to the axial center direction is set onthe side of the circuit board placement base part 52 with respect to thehousing part 51 b. This wall part 51 e is formed of a plate-shaped bodywith a predetermined thickness. The housing part 51 b is set to a sizewith which the writing pressure detector 80 to be described later can behoused without protrusion of the writing pressure detector 80 from thishousing part 51 b to the external.

In the part on the side of the circuit board placement base part 52relative to the step part 51 d in the tubular part 51 of the holder 50,a cut-out part 51 f illustrated in FIG. 4 and FIG. 5A is formed at thepart on the side of the circuit board placement base part 52 relative tothe wall part 51 e. Furthermore, as illustrated in FIG. 3B, FIG. 4, andFIG. 5A, in this example, a part extending to the part of the wall part51 e is formed into a flat surface shape continuously with the flatsurface part 52 a of the circuit board placement base part 52 in thetubular part 51 at the part of the cut-out part 51 f. The width of thecut-out part 51 f in a direction orthogonal to the axial centerdirection is selected to be wider than the width of a line part 94 ofthe circuit board 90 to be described later.

In the state in which the holder 50 is housed in the cartridge chassiscomponent 60 and both are joined, the opening part 51 bm of the housingpart 51 b and the cut-out part 51 f are covered by the cartridge chassiscomponent 60.

Furthermore, in this embodiment, on the surface (curved surface) of theholder 50 on the opposite side to the flat surface part 52 a, asillustrated in FIG. 5B, two terminal members 53 and 54 (for facilitationof understanding, illustrated with slashes in FIGS. 5A and 5B) forconnecting both ends of the coil 41 to the circuit board 90 are formedin the axial center direction of the electronic pen 1 from the pen tipside to an intermediate part of the circuit board placement base part 52across the step part 51 d as a three-dimensional micro-pattern using amolded interconnect device (MID) technique. As a result, the terminalmembers 53 and 54 become the state of being formed monolithically withthe holder 50. As illustrated in FIG. 4 and FIG. 5A, the terminalmembers 53 and 54 are formed in such a manner that end parts 53 a and 54a thereof appear also at the flat surface part 52 a of the circuit boardplacement base part 52.

Moreover, the terminal members 53 and 54 are extended also to the pentip side relative to the step part 51 d in the tubular part 51 of theholder 50. Therefore, also when the cartridge chassis component 60 andthe holder 50 are joined, the state in which the part extended also tothe pen tip side relative to the step part 51 d is exposed to theexternal is obtained. Both ends of the coil 41 are electricallyconnected to these terminal members 53 and 54 exposed to the external bybeing soldered, for example.

Next, the circuit board 90 will be described. FIG. 5C and FIG. 5D arediagrams when the circuit board 90 is viewed from the side of thesurface on which a conductor pattern is formed. FIG. 5C illustrates thestate before the writing pressure detector 80 is placed on the circuitboard 90 and FIG. 5D illustrates the state in which the writing pressuredetector 80 is placed on the circuit board 90 and is electricallyconnected to be fixed. Furthermore, FIG. 5E is a diagram illustratingthe state in which the holder 50 is caused to hold the circuit board 90.

The circuit board 90 is configured with use of a flexible substrate 91with an elongated shape. Along the longitudinal direction of theflexible substrate 91, the circuit board 90 is configured to, asillustrated in FIG. 4 and FIGS. 5C and 5D, include a circuit element forgenerating writing pressure information from detection output of thewriting pressure detector 80 and include a circuit placement part 92including circuit elements configuring a circuit (in this example,resonant circuit) for sending out a signal for position detection to theposition detecting device, a writing pressure detector placement part 93on which the writing pressure detector 80 is placed, and the line part94 between the circuit placement part 92 and the writing pressuredetector placement part 93.

The length of the part of the circuit placement part 92 of the flexiblesubstrate 91 in the longitudinal direction is selected to be almostequal to the length of the flat surface part 52 a of the circuit boardplacement base part 52 of the holder 50 in the longitudinal direction.Furthermore, the width thereof (length in a direction orthogonal to thelongitudinal direction (hereinafter the same)) is set identical to thewidth of the circuit board placement base part 52 of the holder unit 50in this example. However, the width of the part of the circuit placementpart 92 may be smaller than the width of the circuit board placementbase part 52.

The width of the part of the writing pressure detector placement part 93of the flexible substrate 91 is set smaller than the width of the partof the circuit placement part 92 in this example. Furthermore, thelength of the part of the writing pressure detector placement part 93 inthe longitudinal direction of the flexible substrate 91 is set to alength with which the whole is housed in the housing part 51 b. The partof the writing pressure detector placement part 93 of the flexiblesubstrate 91 is formed into a square shape in conformity to the shape ofthe writing pressure detector 80 to be described later in this example.The size of the writing pressure detector placement part 93 may be thesame as or slightly larger than the size of the writing pressuredetector 80.

The length of the part of the line part 94 of the flexible substrate 91in the longitudinal direction is selected to be slightly longer than thelength of the cut-out part 51 f of the tubular part 51 of the holder 50.Furthermore, the width of the part of the line part 94 of the flexiblesubstrate 91 is selected to be smaller than the width of the writingpressure detector placement part 93 and be thinner than the width of thecut-out part 51 f, and the configuration is made in such a manner thatit becomes easier for the flexible substrate 91 to be folded at the partof this line part 94.

In the circuit placement part 92, on one surface (front surface) 91 a ofthe flexible substrate 91, capacitors 95 a, 95 b, and 95 c that areconnected in parallel to the coil 41 of the signal transmitter 40 andform a resonant circuit are disposed as illustrated in FIGS. 5C and 5D.In addition, a conductor pattern for a circuit composed of conductorpatterns 96 a and 96 b for forming the resonant circuit by connectingthe coil 41 and these capacitors 95 a, 95 b, and 95 c in parallel, andso forth, is disposed.

In the circuit placement part 92 of the flexible substrate 91, cut-outparts 92 a and 92 b are formed as illustrated in FIGS. 5C and 5D atparts corresponding to the end part 53 a of the terminal member 53 andthe end part 54 a of the terminal member 54 when the circuit placementpart 92 is placed on the flat surface part 52 a of the circuit boardplacement base part 52 of the holder 50. Furthermore, the conductorpatterns 96 a and 96 b are formed also at the parts of these cut-outparts 92 a and 92 b as illustrated in FIGS. 5C and 5D.

Therefore, as illustrated in FIG. 5E, when the circuit board 90 isplaced on the circuit board placement base part 52 of the holder 50, theend part 53 a of the terminal member 53 and the end part 54 a of theterminal member 54 and the conductor patterns 96 a and 96 b are set topositions close to each other. Thus, electrical connection can be mademore easily by soldering, for example, between the end part 53 a of theterminal member 53 and the conductor pattern 96 a and between the endpart 54 a of the terminal member 54 and the conductor pattern 96 b.

At the line part 94, as illustrated in FIGS. 5C and 5D, line patterns(conductor patterns) 941 and 942 electrically connected to the conductorpatterns 96 a and 96 b, respectively, of the circuit placement part 92are formed between the circuit placement part 92 and the writingpressure detector placement part 93. Furthermore, at the writingpressure detector placement part 93, as illustrated in FIG. 5C,electrically-conductive pad patterns 931 and 932 electrically connectedto the conductor patterns 96 a and 96 b, respectively, of the circuitplacement part 92 through the line patterns 941 and 942 of the line part94 are formed. The electrically-conductive pad patterns 931 and 932 arefor electrical connection to the writing pressure detector 80.

In the example of FIGS. 5C and 5D, a capacitor 95 d is connected betweenthe conductor pattern 96 b of the circuit placement part 92 and the linepattern 942 of the line part 94.

In the circuit board 90 of this example, only on one surface side (frontsurface side) of the flexible substrate 91, the necessary conductorpattern is formed and the circuit elements connected through theconductor pattern are disposed. Furthermore, in this example, adouble-sided tape (diagrammatic representation is omitted in FIG. 5) isstuck to the other surface side (back surface side) of the circuitplacement part 92 of the flexible substrate 91 of the circuit board 90.In this example, the double-sided tape is not stuck to the back surfaceside of the writing pressure detector placement part 93 and the linepart 94 of the flexible substrate 91. However, the double-sided tape maybe stuck thereto.

In this example, the writing pressure detector 80 is formed of a singlecomponent configured as a package with use of a microelectromechanicalsystem (MEMS) element that detects the pressure applied to the core bodyas change in the capacitance.

FIGS. 6A and 6B depict diagrams for explaining the configuration of thewriting pressure detector 80 of this example. FIG. 6A is a plan view asviewed from the side of the pressure receiving part thereof. FIG. 6B isa sectional view along line A-A in FIG. 6A.

The writing pressure detector 80 of this example is what is obtained bysealing a pressure sensing chip 81 configured as a semiconductor devicefabricated by a MEMS technique in a package 82 with a rectangularparallelepiped box shape, for example.

The pressure sensing chip 81 detects the applied pressure as change inthe capacitance. The pressure sensing chip 81 of this example is formedinto a rectangular parallelepiped shape of depth×width×height=L1×L1×H1.For example, L1=1.5 mm and H1=0.5 mm are set.

The pressure sensing chip 81 of this example is composed of a firstelectrode 811, a second electrode 812, and an insulating layer(dielectric layer) 813 between the first electrode 811 and the secondelectrode 812. The first electrode 811 and the second electrode 812 areformed of a conductor composed of single-crystal silicon (Si) in thisexample. The insulating layer 813 is formed of an oxide film (SiO₂) inthis example.

Furthermore, on the side of the surface of this insulating layer 813opposed to the first electrode 811, a circular recess 814 centered atthe central position of this surface is formed in this example. A space815 is formed between the insulating layer 813 and the first electrode811 due to this recess 814. In this example, the bottom surface of therecess 814 is formed as a flat surface and a radius R thereof is set toR=1 mm, for example. Moreover, the depth of the recess 814 is set toseveral tens of microns to approximately one hundred microns in thisexample.

Due to the existence of this space 815, the first electrode 811 can bedisplaced to bend in the direction of this space 815 when being pressedfrom the side of a surface 811 a on the opposite side to the surfaceopposed to the second electrode 812. The thickness of the single-crystalsilicon as an example of the first electrode 811 is set to a thicknessthat allows bending by the applied pressure and is set thinner than thesecond electrode 812.

In the pressure sensing chip 81 with the above configuration, acapacitor 81C is formed between the first electrode 811 and the secondelectrode 812. Furthermore, when a pressure is applied to the firstelectrode 811 from the side of the surface 811 a of the first electrode811 on the opposite side to the surface opposed to the second electrode812, the first electrode 811 bends and the distance between the firstelectrode 811 and the second electrode 812 becomes shorter, so that thevalue of the capacitance of the capacitor 81C changes to become large.The amount of bending of the first electrode 811 changes according tothe magnitude of the applied pressure. Therefore, the capacitor 81C is avariable-capacitance capacitor according to the magnitude of thepressure applied to the pressure sensing chip 81.

In the writing pressure detector 80 of this embodiment, the pressuresensing chip 81 having the above configuration is housed in the package82 in the state in which the surface 811 a of the first electrode 811that receives a pressure serves as the pressure receiving side.

In this example, the package 82 is composed of a package member 821composed of an electrically-insulating material such as a ceramicmaterial or resin material and an elastic member 822 disposed on theside of the surface 811 a that receives the pressure of the pressuresensing chip 81 in this package member 821.

The package 82 of this example is formed into a rectangularparallelepiped shape of depth×width×height=L2×L2×H2. For example, L2=1.9mm and H2=1.0 mm are set.

Furthermore, as illustrated in FIG. 6B, to the bottom surface of thepackage member 821 of the writing pressure detector 80 on the oppositeside to the pressure receiving side, a first lead terminal 83 connectedto the first electrode 811 of the pressure sensing chip 81 is led outand a second lead terminal 84 connected to the second electrode 812 ofthe pressure sensing chip 81 is led out. The first lead terminal 83 iselectrically connected to the first electrode 811 by a gold wire 85, forexample. Furthermore, the second lead terminal 84 is electricallyconnected to the second electrode 812 by a gold wire 86, for example.

The writing pressure detector 80 is placed on the writing pressuredetector placement part 93 of the circuit board 90 and is fixed onto thewriting pressure detector placement part 93 as illustrated in FIG. 5D insuch a manner that the first lead terminal 83 and the second leadterminal 84 are electrically connected to the electrically-conductivepad patterns 931 and 932, respectively, formed on the writing pressuredetector placement part 93 of the circuit board 90.

In this manner, the circuit board 90 on which the writing pressuredetector 80 is placed on the writing pressure detector placement part 93and is electrically connected and fixed becomes the state in which thecapacitor forming the resonant circuit with the coil 41 and thecapacitor formed of the writing pressure detector 80 are connected inparallel.

The circuit board 90 with the above configuration is manufactured asfollows. Specifically, first, a plurality of parts having theconfiguration of the above-described circuit board 90 in which thenecessary conductor pattern like the above-described one is formed atthe circuit placement part 92, the writing pressure detector placementpart 93, and the line part 94 are formed on a flexible substrate with apredetermined size. At this time, each of the parts having theconfiguration of the above-described circuit board 90 is formed in sucha manner that the plurality of parts are lined up with the intermediaryof a gap with which later separation is possible.

Next, in each of the constituent parts of the plurality of circuit board90, for the circuit placement part 92, solder paste for connectionbetween the formed conductor pattern and the necessary electroniccomponents is applied and the necessary electronic components are placedthrough position alignment. In addition, solder paste is applied to therespective electrically-conductive pad patterns 931 and 932 of thewriting pressure detector placement part 93 and the writing pressuredetector 80 is placed through position alignment between the first leadterminal 83 and the second lead terminal 84 thereof and theelectrically-conductive pad patterns 931 and 932.

Next, the flexible substrate on which the writing pressure detectors 80are placed on these writing pressure detector placement parts 93 isloaded into a solder reflow apparatus and the solder paste on theflexible substrate is melted to make electrical connection between theelectronic components of the circuit placement part 92 and the conductorpattern and make electrical connection between theelectrically-conductive pad patterns 931 and 932 of the writing pressuredetector placement part 93 and the first lead terminal 83 and the secondlead terminal 84 of the writing pressure detector 80. Thereby, thenecessary electronic components are fastened to the circuit placementpart 92 and the writing pressure detector 80 is fastened to the writingpressure detector placement part 93.

Next, the flexible substrate is cut in such a manner that the parts ofthe plurality of circuit boards 90 are separated from each other andeach of the circuit boards 90 with the above-described configuration iscompleted.

For the circuit board 90 manufactured in the above-described manner, asillustrated in FIG. 7, the part of the writing pressure detectorplacement part 93 on which the writing pressure detector 80 is placedand is electrically connected and fixed is let in and inserted into thehousing part 51 b and housed through the opening part 51 bm of thetubular part 51 of the holder 50 from the direction that is orthogonalto the axial center direction and is orthogonal to the flat surface part52 a of the circuit board placement base part 52 of the holder 50. Then,as illustrated in FIG. 7 and FIG. 5D, the circuit board 90 is folded atthe place of the line part 94 and the part of the circuit placement part92 is pressed against the side of the flat surface part 52 a of thecircuit board placement base part 52. At this time, the line part 94 canbe located on the side of the flat surface part 52 a of the circuitboard placement base part 52 through the cut-out part 51 f of the holder50 (see FIG. 3B and FIG. 5D).

Then, as illustrated in FIG. 7, by a double-sided tape 97 disposed onthe back surface side of the flexible substrate 91 of the circuit board90, the writing pressure detector placement part 93 is boned and fixedto the surface of the wall part 51 e on the side of the housing part 51b and the circuit placement part 92 is bonded and fixed onto the flatsurface part 52 a of the circuit board placement base part 52 of theholder 50. A protrusion 52 b for clamping and locking an end part of thecircuit board 90 in the longitudinal direction is formed on the rear endside of the circuit board placement base part 52. The circuit board 90is disposed on the flat surface part 52 a of the circuit board placementbase part 52 in such a manner that the end part is clamped between thisprotrusion 52 b and the flat surface part 52 a of the circuit boardplacement base part 52.

In the example of FIG. 3B, the line part 94 is set to the state in whichit exists in the air. However, needless to say, this line part 94 mayalso be bonded and fixed to the surface of the wall part 51 e on theopposite side to the side of the housing part 51 b and an extended flatsurface of the circuit placement part 92 by a double-sided tape.

After the circuit board 90 is held by the holder 50 in theabove-described manner, the holder 50 is housed into the cartridgechassis component 60 from the opposite side to the tubular part 51 andthe state is made in which the end surface of the cartridge chassiscomponent 60 abuts against the step part 51 d of the tubular part 51 ofthe holder 50 as described above. Thereby, the holder 50 is joined tothe cartridge chassis component 60 in the state in which the cut-outpart 51 f and the opening part 51 bm of the housing part 51 b in thetubular part 51 of the holder 50 are covered by the cartridge chassiscomponent 60.

Thereafter, the pressure transmitting component 31 around which the coilspring 32 is wound is inserted into the penetration hole 51 c of thetubular part 51 of the holder 50. Then, the ferrite core 42 and the corepipe member 43 of the signal transmitter 40 are inserted and fitted intothe tubular part 51 of the holder 50 and the signal transmitter 40 isjoined to the holder 50. Then, one end and the other end of the coil 41wound around the ferrite core 42 of the signal transmitter 40 areelectrically connected to the terminal members 53 and 54 formed on thetubular part 51 of the holder 50 by soldering or the like, for example.

Thereafter, the core body 30 is inserted in the penetration hole 43 c ofthe core pipe member 43 and the end part 30 b of the core body 30 isinserted and fitted into the fitting recess 31 c of the pressuretransmitting component 31. Through the above, the electronic pen mainbody 3 is completed.

In the above-described manner, in this embodiment, the circuit board 90includes the writing pressure detector placement part 93 and the writingpressure detector 80 is placed on the writing pressure detectorplacement part 93 in advance and is fixed in the state of beingelectrically connected to a circuit element of the circuit placementpart 92 of the circuit board 90. Therefore, the electrical connectionbetween the writing pressure detector 80 and the circuit placement part92 has already ended at a stage before the holder 50 is caused to holdthe circuit board 90. For this reason, a step of connecting the writingpressure detector and the circuit board by soldering or the like afterthe holder 50 is caused to hold the circuit board 90 as in theconventional technique becomes unnecessary

Circuit Configuration for Position Detection and Writing PressureDetection in Position Detecting Device Used with Electronic Pen 1

Next, with reference to FIG. 8, a description will be made regarding acircuit configuration example of a position detecting device 400 thatcarries out detection of the position indicated by the electronic pen 1of the above-described embodiment and detection of the writing pressureapplied to the electronic pen 1 and the operation of the positiondetecting device 400.

As illustrated in FIG. 8, the electronic pen 1 includes a resonantcircuit in which the coil 41 as an inductance element, thevariable-capacitance capacitor 81C formed of the pressure sensing chip81 of the writing pressure detector 80, and a capacitor Cf for resonancedisposed at the circuit placement part 92 of the circuit board 90 areconnected in parallel. The capacitor Cf is illustrated as what isobtained by combining the capacitors 95 a, 95 b, and 95 c disposed atthe circuit placement part 92 of the circuit board 90. Furthermore, itis assumed that the capacitor 95 d of the circuit placement part 92 ofthe circuit board 90 is included in the variable-capacitance capacitor81C for convenience of description.

Meanwhile, in the position detecting device 400, an X-axis directionloop coil group 411 and a Y-axis direction loop coil group 412 arestacked and a position detecting coil 410 is formed. The respective loopcoil groups 411 and 412 are composed of n and m, respectively,rectangular loop coils, for example. The respective loop coilsconfiguring the respective loop coil groups 411 and 412 are disposed tobe lined up at equal intervals and sequentially overlap with each other.

Furthermore, in the position detecting device 400, a selection circuit413 to which the X-axis direction loop coil group 411 and the Y-axisdirection loop coil group 412 are connected is disposed. This selectioncircuit 413 sequentially selects one loop coil in the two loop coilgroups 411 and 412.

Moreover, the position detecting device 400 is provided with anoscillator 421, a current driver 422, a switching connecting circuit423, a receiving amplifier 424, a detector 425, a low-pass filter 426, asample/hold circuit 427, an analog to digital (A/D) conversion circuit428, a synchronous detector 429, a low-pass filter 430, a sample/holdcircuit 431, an A/D conversion circuit 432, and a central processingunit (CPU) 433. The central processing unit 433 is formed of amicroprocessor.

The oscillator 421 generates an AC signal with a frequency f0.Furthermore, the oscillator 421 supplies the generated AC signal to thecurrent driver 422 and the synchronous detector 429. The current driver422 converts the AC signal supplied from the oscillator 421 to a currentand sends out the current to the switching connecting circuit 423. Basedon control from the central processing unit 433, the switchingconnecting circuit 423 switches the connection target (transmitting-sideterminal T, receiving-side terminal R) to which the loop coil selectedby the selection circuit 413 is connected. In these connection targets,the transmitting-side terminal T and the receiving-side terminal R areconnected to the current driver 422 and the receiving amplifier 424,respectively.

An induced voltage generated in the loop coil selected by the selectioncircuit 413 is sent to the receiving amplifier 424 via the selectioncircuit 413 and the switching connecting circuit 423. The receivingamplifier 424 amplifies the induced voltage supplied from the loop coiland sends out the amplified voltage to the detector 425 and thesynchronous detector 429.

The detector 425 detects the induced voltage generated in the loop coil,i.e., the received signal, and sends out the received signal to thelow-pass filter 426. The low-pass filter 426 has a cutoff frequencysufficiently lower than the above-described frequency f0 and convertsthe output signal of the detector 425 to a DC signal to send out the DCsignal to the sample/hold circuit 427. The sample/hold circuit 427 holdsa voltage value at predetermined timing of the output signal of thelow-pass filter 426, specifically at predetermined timing in thereception period, and sends out the voltage value to the A/D conversioncircuit 428. The A/D conversion circuit 428 converts the analog outputof the sample/hold circuit 427 to a digital signal and outputs thedigital signal to the central processing unit 433.

Meanwhile, the synchronous detector 429 carries out synchronousdetection of the output signal of the receiving amplifier 424 with theAC signal from the oscillator 421 and sends out a signal at a levelaccording to the phase difference between them to the low-pass filter430. This low-pass filter 430 has a cutoff frequency sufficiently lowerthan the frequency f0 and converts the output signal of the synchronousdetector 429 to a DC signal to send out the DC signal to the sample/holdcircuit 431. This sample/hold circuit 431 holds a voltage value atpredetermined timing of the output signal of the low-pass filter 430 andsends out the voltage value to the A/D conversion circuit 432. The A/Dconversion circuit 432 converts the analog output of the sample/holdcircuit 431 to a digital signal and outputs the digital signal to thecentral processing unit 433.

The central processing unit 433 controls the respective units of theposition detecting device 400. Specifically, the central processing unit433 controls selection of the loop coil in the selection circuit 413,switching by the switching connecting circuit 423, and the timing of thesample/hold circuits 427 and 431. The central processing unit 433 causesradio waves to be transmitted from the X-axis direction loop coil group411 and the Y-axis direction loop coil group 412 with a certaintransmission continuation time (continuous transmission section) basedon input signals from the A/D conversion circuits 428 and 432.

In each loop coil of the X-axis direction loop coil group 411 and theY-axis direction loop coil group 412, an induced voltage is generated byradio waves transmitted (returned) from the electronic pen 1. Thecentral processing unit 433 calculates the coordinate value of theposition indicated by the electronic pen 1 in the X-axis direction andthe Y-axis direction based on the level of the voltage value of thisinduced voltage generated in each loop coil. Furthermore, the centralprocessing unit 433 detects the writing pressure based on the level of asignal according to the phase difference between transmitted radio wavesand received radio waves.

In this manner, the position of the electronic pen 1 that approaches isdetected by the central processing unit 433 in the position detectingdevice 400. Furthermore, information on the writing pressure value ofthe electronic pen 1 is obtained by detecting the phase of a receivedsignal.

Effects of First Embodiment

In the electronic pen 1 of the above-described embodiment, the circuitboard 90 obtained by forming the circuit placement part 92, the writingpressure detector placement part 93, and the line part 94 between thecircuit placement part 92 and the writing pressure detector placementpart 93 on the flexible substrate 91 in the longitudinal directionthereof is used, and the writing pressure detector 80 is placed on thewriting pressure detector placement part 93 in advance and is fixed inthe state of being electrically connected to a circuit element of thecircuit placement part 92 through the line part 94. Therefore, theelectrical connection between the writing pressure detector 80 and thecircuit placement part 92 has already ended at a stage before the holderunit 50 is caused to hold the circuit board 90, and a step of solderingprocessing for electrically connecting the writing pressure detector 80and the circuit element of the circuit placement part 92 can be reduced.

Furthermore, the circuit board 90 is formed of the flexible substrate 91and can be bent at the part of the line part 94. This provides an effectthat the writing pressure detector 80 can be housed in the housing part51 b of the tubular part 51 of the holder unit 50, with the pressurereceiving surface of the writing pressure detector 80 along thedirection orthogonal to the axial center direction, such that thepressure applied to the core body 30 can be received.

Moreover, because the pressure sensing chip 81 is disposed as onecomponent housed in the package 82, there is also an effect that thewriting pressure detector 80 can be attached by only placing the writingpressure detector 80 on the writing pressure detector placement part 93of the circuit board 90 and fixing the terminal members of the pressuresensing chip 81 in the state in which the terminal members areelectrically connected to the electrically-conductive pad patterns ofthe writing pressure detector placement part 93.

Furthermore, the terminal members 53 and 54 for electrical connectionbetween both ends of the coil 41 and the circuit elements of the circuitplacement part 92 are formed on the holder unit 50. Therefore, there isan effect that the electrical connection between both ends of the coil41 and the circuit elements of the circuit placement part 92 is allowedat the holder unit 50 and connection work becomes easy.

Second Embodiment

In the electronic pen 1 of the above-described first embodiment, theterminal members 53 and 54 are formed on the tubular part 51 of theholder unit 50 as a three-dimensional micro-pattern for connectionbetween the coil 41 and circuit elements of the circuit placement part92 of the circuit board 90. However, the connection between the coil 41and the circuit elements of the circuit placement part 92 of the circuitboard 90 is not limited to such a form. In an electronic pen of a secondembodiment, the configuration is made in such a manner that a circuitboard 90 and both ends of the coil 41 can be directly connected byslightly changing the configuration of the holder unit 50 and thecircuit board 90 of the electronic pen main body 3 in the firstembodiment.

FIGS. 9A-9D depict diagrams illustrating a holder 50A and a circuitboard 90A that configure the major part of the electronic pen of thissecond embodiment and the other part of the electronic pen of the secondembodiment is configured similarly to the first embodiment. In theholder 50A and the circuit board 90A of the example of FIGS. 9A-9D, thesame part as the holder 50 and the circuit board 90 of the electronicpen 1 of the above-described first embodiment is given the samereference numeral and detailed description thereof is omitted.

FIG. 9A is a diagram of the holder 50A when a flat surface part 52Aa ofa circuit board placement base part 52A is viewed from directly above.Furthermore, FIG. 9B is a diagram when the holder 50A is viewed from theopposite side to the side of the flat surface part 52Aa of the circuitboard placement base part 52A. Moreover, FIG. 9C is a diagram when thecircuit board 90A is viewed from the side of a front surface 91Aa of aflexible substrate 91A. FIG. 9D is a diagram when the circuit board 90Ais viewed from the side of a back surface 91Ab of the flexible substrate91A.

As illustrated in FIG. 9A, the configuration of the holder 50A when theflat surface part 52Aa of the circuit board placement base part 52A isviewed from directly above is only different in that the end parts 53 aand 54 a of the terminal members 53 and 54 do not exist, and is the sameas the holder 50 in the electronic pen 1 of the first embodiment. In thesecond embodiment, the configuration of the holder 50A on the oppositeside to the flat surface part 52Aa of the circuit board placement basepart 52A is different from the holder 50 of the first embodiment.

Specifically, as illustrated in FIG. 9B, on the opposite side to theside of the flat surface part 52Aa of the circuit board placement basepart 52A in a tubular part 51A of the holder 50A in this secondembodiment, a groove 51 g with a V-shape for preventing one end 41 a andthe other end 41 b of the coil 41 from protruding from the sidecircumferential surface of the tubular part 51A is formed along theaxial center direction. In addition, an opening recess 51 h thatcommunicates with the housing part 51 b of the writing pressure detector80 is formed. The groove 51 g is formed from the pen tip side of thetubular part 51A to the position of the opening recess 51 h.

In this case, the opening recess 51 h is formed on the side of thecircuit board placement base part 52A relative to the position of thestep part 51 d of the holder 50A in the axial center direction.Therefore, this opening recess 51 h becomes the state of being coveredby the cartridge chassis component 60 when the cartridge chassiscomponent 60 and the holder 50A are joined.

As illustrated in FIG. 9C, the flexible substrate 91A of the circuitboard 90A of this second embodiment includes an extending part 98 thatfurther extends from the writing pressure detector placement part 93 inthe longitudinal direction. This extending part 98 is configured in sucha manner that the width of the connecting part to the writing pressuredetector placement part 93 is small, and is set to easily bend at thispart.

On the front surface 91Aa of the flexible substrate 91A in thisextending part 98, line patterns 981 and 982 connected to theelectrically-conductive pad patterns 931 and 932, respectively, formedat the writing pressure detector placement part 93 are formed.Furthermore, at the extending part 98, as illustrated in FIG. 9C andFIG. 9D, the line patterns 981 and 982 on the front surface 91Aa of theflexible substrate 91A are connected to electrically-conductive pads 985and 986 on a back surface 91Ab of the flexible substrate 91A viathrough-holes 983 and 984, respectively. In this example, a double-sidedtape 97 a is disposed on the side of the front surface 91Aa of theflexible substrate 91A in the extending part 98 although diagrammaticrepresentation is omitted.

In an electronic pen 1A of this second embodiment, as illustrated inFIG. 10A, the circuit board 90A is bent at the part of the line part 94.In addition, the part of the extending part 98 can also be bent withrespect to the writing pressure detector placement part 93.

FIG. 10B illustrates a sectional view of a joining part between thesignal transmitter 40 of the electronic pen 1A of this second embodimentand the holder 50A. In this second embodiment, the circuit board 90A isbent at the place of the line part 94 as illustrated in FIG. 10Asimilarly to the first embodiment, and the writing pressure detectorplacement part 93 to which the writing pressure detector 80 is attachedand the extending part 98 are inserted into the housing part 51 b fromthe opening part 51 bm of the tubular part 51A of the holder 50A from adirection orthogonal to the axial center direction.

Then, as illustrated in FIG. 10B, the extending part 98 is located inthe opening recess 51 h that communicates with the housing part 51 b. Inthis state, the writing pressure detector placement part 93 is bonded tothe wall part 51 e by the double-sided tape and thereby the writingpressure detector 80 is housed in the housing part 51 b in the state inwhich it can receive the pressure applied to the core body 30.

Then, the extending part 98 is fixed to the bottom part of the openingrecess 51 h through bonding of the front surface 91Aa of the flexiblesubstrate 91A by the double-sided tape. Then, as illustrated in FIG.10C, the state is obtained in which the electrically-conductive pads 985and 986 formed on the side of the back surface 91Ab of the flexiblesubstrate 91A in the extending part 98 are exposed from the openingrecess 51 h of the tubular part 51A of the holder 50.

Then, the ferrite core 42 and the core pipe member 43 of the signaltransmitter 40 are fitted into the tubular part 51A of the holder 50Aand the signal transmitter 40 is joined to the holder 50A. Thereafter,as illustrated in FIGS. 10B and 10C, the one end 41 a and the other end41 b of the coil 41 wound around the ferrite core 42 are led to theplace of the opening recess 51 h along the inside of the V-shaped groove51 g of the tubular part 51A. Then, the one end 41 a and the other end41 b of the coil 41 are electrically connected to theelectrically-conductive pads 985 and 986, respectively, exposed in theopening recess 51 h by soldering or the like, for example.

In the above-described manner, according to this second embodiment, theextending part 98 is disposed in the circuit board 90A and electricalconnection to the one end 41 a and the other end 41 b of the coil 41 canbe directly carried out in this extending part 98. Due to this, theterminal members 53 and 54 formed on the tubular part 51 by using an MIDtechnique as in the case of the electronic pen 1 of the first embodimentcan be made unnecessary.

Modification Examples of Second Embodiment First Modification Example

In the electronic pen 1A of the above-described second embodiment, theopening recess 51 h that exposes the extending part 98 to the externalis formed on the pen tip side of the housing part 51 b. Thus, in theflexible substrate 91A of the circuit board 90A, the extending part 98is bent to extend to the pen tip side as illustrated in FIG. 10A, andthe state is made in which the side of the back surface 91Ab of theflexible substrate 91A in the extending part 98 is exposed from theopening recess 51 h. For this reason, in the above-described secondembodiment, the electrically-conductive pads 985 and 986 connected tothe line patterns 981 and 982 on the side of the front surface 91Aa viathe through-holes 983 and 984 need to be formed on the side of the backsurface 91Ab in the extending part 98.

The electronic pen 1B of an example of FIG. 11A is an example in whichthe configuration is made to eliminate the need to form a conductorpattern on the back surface side of the flexible substrate 91A in theextending part 98 of the circuit board 90A. This FIG. 11A illustrates asectional view of a joining part between the signal transmitter 40 ofthe electronic pen 1B of this second embodiment and a holder 50B. In theelectronic pen 1B of the example of this FIG. 11A, the same part as theelectronic pen 1A of the second embodiment is given the same referencenumeral and detailed description thereof is omitted.

In the electronic pen 1B of the example of this FIG. 11A, an openingrecess 51 hB that communicates with the housing part 51 b of a tubularpart 51B of the holder 50B is made on the side of a circuit boardplacement base part 52B of the holder 50B relative to the housing part51 b. If this is employed, when the writing pressure detector placementpart 93 of a circuit board 90B is housed in the housing part 51 b, anextending part 98B thereof becomes the state in which the side of thefront surface 91Aa of the flexible substrate 91A is exposed through theopening recess 51 hB.

Therefore, in the electronic pen 1B of this example, in the extendingpart 98B of the circuit board 90B, electrically-conductive pads 987 and988 are formed on the side of the front surface 91Aa of the flexiblesubstrate 91A instead of the line patterns 981 and 982 as illustrated inFIG. 11A, and the through-holes 983 and 984 and theelectrically-conductive pads 985 and 986 on the back surface 91Ab arenot made. Furthermore, a V-shaped groove 51 gB formed in the tubularpart 51B of the holder 50B is formed from the pen tip side of thetubular part 51B to the position of the opening recess 51 hB.

Then, after the ferrite core 42 and the core pipe member 43 of thesignal transmitter 40 are fitted into the holder 50B, the one end 41 aand the other end 41 b of the coil 41 are led to the opening recess 51hB along the inside of the groove 51 gB. Then, the one end 41 a and theother end 41 b of the coil 41 are electrically connected to theelectrically-conductive pads 987 and 988, respectively, exposed in theopening recess 51 hB by soldering or the like, for example.

In this case, the opening recess 51 hB is formed on the side of thecircuit board placement base part 52B relative to the position of thestep part 51 d of the holder 50B in the axial center direction.Therefore, this opening recess 51 hB becomes the state of being coveredby the cartridge chassis component 60 when the cartridge chassiscomponent 60 and the holder 50B are joined.

According to the example of this FIG. 11A, there is an effect that itsuffices to only generate a conductor pattern for electrical connectionon a single surface side of the flexible substrate 91A of the circuitboard 90B.

Second Modification Example

FIG. 11B is a diagram for explaining an electronic pen 1C of a secondexample of the modification examples of the second embodiment. This FIG.11B also illustrates a sectional view of a joining part between thesignal transmitter 40 of the electronic pen 1C of this example and aholder 50C.

In the electronic pen 1C of this second example, as a circuit board 90C,a configuration that does not have the extending part 98 but includesthe circuit placement part 92, the writing pressure detector placementpart 93, and the line part 94 similarly to the circuit board 90 in theelectronic pen 1 of the first embodiment is employed. However, in thecircuit board 90C of this second example, through-holes 99 a and 99 bconnected to the conductor patterns 96 a and 96 b are formed atlongitudinal-direction positions at which the cut-out parts 92 a and 92b of the circuit board 90 are formed in the first embodiment asillustrated in FIG. 11B.

Furthermore, penetration holes 55 a and 55 b that penetrate from theback side of a flat surface part 52 aC to the flat surface part 52 aCare formed at the positions at which the through-holes 99 a and 99 b arelocated when the circuit board 90C is placed on the flat surface part 52aC in a circuit board placement base part 52C of the holder 50C.Moreover, a V-shaped groove 51 gC formed in the holder 50C is formedfrom the pen tip side to the positions at which the penetration holes 55a and 55 b are formed in the axial center direction.

In addition, in the electronic pen 1C of this second example, asillustrated in FIG. 11B, the one end 41 a and the other end 41 b of thesignal transmitter 40 are led to the positions at which the penetrationholes 55 a and 55 b are formed along the inside of the groove 51 gC.Moreover, the one end 41 a and the other end 41 b are led out to theside of a front surface 91 aC of a flexible substrate 91C of the circuitboard 90C via the penetration holes 55 a and 55 b, respectively, and viathe through-holes 99 a and 99 b of the circuit board 90C. Then, on thefront surface 91 aC of a flexible substrate 91C in a circuit placementpart 92C of the circuit board 90C, the one end 41 a and the other end 41b are electrically connected to the conductor patterns 96 a and 96 b bysoldering or the like, for example.

Third Modification Example

In the electronic pen 1A of the second embodiment and the electronic pen1B of the first example of the modification examples, the extendingparts 98 and 98B are formed to extend from the writing pressure detectorplacement part 93 in the longitudinal direction in the circuit boards90A and 90B. However, as illustrated in FIG. 11C, a circuit board 90Dmay be formed in such a manner that an extending part 98D that extendsthe flexible substrate 91 from the writing pressure detector placementpart 93 is extended in not the longitudinal direction but the short-sidedirection of the circuit board 90.

In the case of this third example, an opening recess is formed in adirection orthogonal to the direction in which the opening part 51 bm ofthe housing part 51 b is oriented in a holder 50D (not illustrated), andthe extending part 98D is exposed to the external from the openingrecess. Furthermore, a V-shaped groove of a tubular part 51D (notillustrated) of the holder 50D is also formed to correspond to theopening recess.

Third Embodiment

In the above-described embodiments, one package component using a MEMSelement is employed as the writing pressure detector. However, theconfiguration of the writing pressure detector is not limited thereto. Athird embodiment is the case of using a writing pressure detector with aconfiguration that includes first and second electrodes that sandwich adielectric and detects the writing pressure as change in the capacitanceby changing the contact area between the first electrode and thedielectric according to the pressure applied to a core body (refer toPatent Document 1).

In this third embodiment, only the configuration of the writing pressuredetector and the configuration of a tubular part of a holder unit changeand the other configuration is formed similarly to the above-describedembodiments. FIGS. 12A and 12B depict diagrams for explaining theconfiguration of a writing pressure detector 80E and a holder 50E in anelectronic pen 1E of this third embodiment. FIG. 12A is a diagram thatillustrates the writing pressure detector 80E in a disassembled mannerin consideration of assembling into the holder 50E and illustrates thepart of the tubular part 51E that houses and holds this writing pressuredetector 80E. Furthermore, FIG. 12B is a longitudinal sectional view inthe state in which the writing pressure detector 80E is housed and heldin the tubular part 51E of the holder 50E. In FIG. 12, the same part asthe electronic pen 1 of the above-described first embodiment is giventhe same reference numeral.

The writing pressure detector 80E of this example also forms acapacitance-variable capacitor whose capacitance changes according tothe writing pressure applied to the core body. As illustrated in FIGS.12A and 12B, the writing pressure detector 80E of this example iscomposed of a plurality of components of a dielectric 801, a terminalmember 802, a holding member 803, an electrically-conductive member 804,and a coil spring 805. The terminal member 802 forms the first electrodeof the capacitance-variable capacitor formed of the writing pressuredetector 80E. Furthermore, the electrically-conductive member 804 andthe coil spring 805 are electrically connected to form the secondelectrode of the capacitance-variable capacitor.

Meanwhile, as illustrated in FIGS. 12A and 12B, the tubular part 51E ofthe holder 50E of this example includes a housing part 51 bE having anopening part 51 bmE oriented in a direction orthogonal to the axialcenter direction. In addition, the tubular part 51E has a configurationin which the plurality of components configuring the writing pressuredetector 80E are lined up in the axial center direction and are housedin this housing part 51 bE and the hollow part of the tubular part 51Ethat communicates with this housing part 51 bE.

As illustrated in FIG. 12A, the dielectric 801 is formed into a plateshape having diameter and thickness that allow the dielectric 801 to behoused in the housing part 51 bE of the tubular part 51E of the holder50E. Furthermore, the terminal member 802 is formed of acircular-disc-shaped electrically-conductive member, for example, aplate-shaped body of an electrically-conductive metal, having diameterand thickness that allow the terminal member 802 to be housed in thehousing part 51 bE of the tubular part 51E of the holder 50E togetherwith the dielectric 801 in the state of being in contact with onesurface side of the dielectric 801 in the axial center direction.

Furthermore, in this third embodiment, the terminal member 802 is placedon a writing pressure detector placement part 93E of a circuit board 90Eand is electrically connected to an electrically-conductive pad formedon this writing pressure detector placement part 93E and is fixed. Inthe circuit board 90E in this third embodiment, oneelectrically-conductive pad electrically connected to the terminalmember 802 is formed on the writing pressure detector placement part93E. Thus, the number of line patterns formed at a line part 94E is setto one. Moreover, at a circuit placement part 92E of the circuit board90E, an electrically-conductive pad connected to the elastic memberconfiguring part of the second electrode of the writing pressuredetector 80E, an end part of the coil spring 805 in this example, isformed as described later. The other configuration of the circuit board90E is the same as the circuit board 90 of the first embodiment.

In the plurality of components configuring the writing pressure detector80E, the dielectric 801 and the terminal member 802, which are thecomponents that do not move in the axial center direction in the hollowpart of the tubular part 51E of the holder 50E, are inserted, asillustrated in FIG. 12A, into the housing part 51 bE of this tubularpart 51E from a direction orthogonal to the axial center directionthrough the opening part 51 bmE oriented in the direction orthogonal tothe axial center direction at the housing part 51 bE of the tubular part51E of the holder 50E, and are housed as illustrated in FIG. 12B.

In this case, the terminal member 802 is fixed to the writing pressuredetector placement part 93E of the circuit board 90E as described above.Thus, similarly to the case of the above-described first embodiment, thecircuit board 90E is bent at the place of the line part 94E asillustrated in FIG. 12A and the writing pressure detector placement part93E fixed to the terminal member 802 is let in the housing part 51 bE.

Then, for the circuit board 90E, as illustrated in FIG. 12B, the part ofthe circuit placement part 92E is placed on a flat surface part 52 aE ofa circuit board placement base part 52E of the holder 50E and thiscircuit placement part 92E is bonded and fixed to the flat surface part52 aE of the circuit board placement base part 52E by a double-sidedtape disposed on the back surface side of the part of the circuitplacement part 92E of the flexible substrate 91E.

As illustrated in FIGS. 12A and 12B, an L-shaped protrusion 802 b thatprotrudes toward the dielectric 801 is formed in the terminal member802. By the L-shaped protrusion 802 b of this terminal member 802, theend part of the dielectric 801 on the side of the opening part 51 bmE ispressed and the dielectric 801 is held so as not to drop off from thehousing part 51 bE.

The holding member 803 forming the writing pressure detector 80Eincludes a circular column shape part 803 a in which a recessed hole 803b into which the core body 30 is press-fitted is made on the side of thecore body 30 in the axial center direction and includes a ring-shapedprotruding part 803 c in which a recessed hole into which theelectrically-conductive member 804 is fitted is made on the oppositeside to the side of the recessed hole 803 b in the axial centerdirection.

The outer diameter (one part in the circumferential direction) of thecircular column shape part 803 a of the holding member 803 is selectedto be slightly smaller than an inner diameter d2 of the hollow part ofthe tubular part 51E. Furthermore, the outer diameter of the ring-shapedprotruding part 803 c of the holding member 803 is selected to besmaller than the outer diameter of the circular column shape part 803 aand be smaller than the inner diameter of the coil spring 805 formingthe elastic member. In this case, a step part is formed between thering-shaped protruding part 803 c and the circular column shape part 803a. This step part is for locking an end part of the coil spring 805.

Furthermore, in this embodiment, engagement protruding parts 803 d and803 e are formed on the side circumferential surface of the circularcolumn shape part 803 a of the holding member 803 and engagement holes51 ia and 51 ib (see FIG. 12B) with which the engagement protrudingparts 803 d and 803 e engage are formed in a side circumferentialsurface of the tubular part 51E of the holder 50E. This allows theholding member 803 to move in the axial center direction thereof even inthe state in which the engagement protruding parts 803 d and 803 e areengaged with the engagement holes 51 ia and 51 ib.

The electrically-conductive member 804 is formed of an elastic memberthat has electrical conductivity and is elastically deformable and iscomposed of silicone conductive rubber or pressure conductive rubber,for example. The center line positions of a larger-diameter part 804 aand a smaller-diameter part 804 b of this electrically-conductive member804 are set identical. Furthermore, the end surface of thelarger-diameter part 804 a on the opposite side to the smaller-diameterpart 804 b is configured to have a curved surface part that bulges intoa bullet shape as illustrated in FIG. 12B.

Furthermore, the coil spring 805 has a wound part 805 a that is formedof a coil spring having electrical conductivity, for example, and haselasticity and a terminal piece 805 b at one end part of this wound part805 a, and has a connecting part 805 c at the other end part of thewound part 805 a. The wound part 805 a of the coil spring is set to havea diameter that allows the electrically-conductive member 804 to behoused in the wound part 805 a without contact and is smaller than thediameter of the circular column shape part 803 a of the holding member803.

The connecting part 805 c of the coil spring 805 is inserted into thebottom part of a recessed hole formed in the ring-shaped protruding part803 c of the holding member 803 (see FIG. 12B). Therefore, when thesmaller-diameter part 804 b of the electrically-conductive member 804 ispress-fitted to the ring-shaped protruding part 803 c of the holdingmember 803, the state is obtained in which the end surface of thesmaller-diameter part 804 b of the electrically-conductive member 804gets contact with the connecting part 805 c of the coil spring 805having electrical conductivity and is electrically connected.

In this third embodiment, first, the dielectric 801 and the terminalmember 802 placed and fixed onto the writing pressure detector placementpart 93E of the circuit board 90E in the components configuring thewriting pressure detector 80E are housed in the housing part 51 bE ofthe tubular part 51E of the holder 50E through the opening part 51 bmE.

Next, in this example, the smaller-diameter part 804 b of theelectrically-conductive member 804 is press-fitted into the recessedhole of the ring-shaped protruding part 803 c of the holding member 803.In addition, the wound part 805 a of the coil spring 805 is disposed tobe brought to the periphery of the ring-shaped protruding part 803 c andthe electrically-conductive member 804.

Next, this unit obtained by combining the holding member 803, theelectrically-conductive member 804, and the coil spring 805 is insertedinto the hollow part of the tubular part 51E in the axial centerdirection from the side of the electrically-conductive member 804through an opening part 51 aE of the tubular part 51E. Then, theengagement protruding parts 803 d and 803 e formed on the circularcolumn shape part 803 a of the holding member 803 are inserted in theaxial center direction until engaging with the engagement holes 5 liaand 5 lib formed in a side circumferential surface of the tubular part51E.

Due to this, irrespective of the biasing force of the coil spring 805 inthe axial center direction, the holding member 803 is locked in thehollow part of the tubular part 51E without dropping off from theopening part 51 aE of the tubular part 51E of the holder 50E.Furthermore, in this state, the dielectric 801 and the terminal member802 are pressed against the side of a wall part 51 eE due to the biasingforce of the coil spring 805 in the axial center direction. Thisprevents the dielectric 801 from dropping off from the opening part 51bmE of the housing part 51 bE of the tubular part 51E.

Next, the terminal piece 805 b of the coil spring 805 is soldered to thecircuit board 90E in the state in which the whole of the plurality ofcomponents configuring the writing pressure detector 80E are housed andlocked in the hollow part and the housing part 51 bE of the tubular part51E of the holder 50E in the above-described manner.

In the writing pressure detector 80E of this example, when a pressure isapplied to the core body 30, the state is obtained in which the holdingmember 803 presses the electrically-conductive member 804 against thedielectric 801 against the elastic biasing force of the coil spring 805according to the applied pressure, and the contact area between thedielectric 801 and the electrically-conductive member 804 changesaccording to the applied pressure. As a result, the capacitance obtainedbetween the terminal member 802 and the terminal piece 805 b of the coilspring 805 changes according to the applied pressure. Thus, similarly tothe above-described first embodiment, the resonant frequency of theresonant circuit composed of the coil 41, the capacitor disposed on thecircuit board 90E, and the writing pressure detector 80E changes and istransmitted to the position detecting device as writing pressureinformation.

In the above-described manner, in the electronic pen 1E of the thirdembodiment, the terminal member 802 forming one electrode of thevariable-capacitance capacitor forming the writing pressure detector 80Eis placed on the writing pressure detector placement part 93E of thecircuit board 90E in advance and is electrically connected and fixed.Therefore, an effect is provided that, after the tubular part 51E of theholder 50E is caused to hold the writing pressure detector 80E, a stepof electrical connection by soldering between the terminal member 802and the circuit board 90E becomes unnecessary although a step ofelectrical connection by soldering between the terminal piece 805 b ofthe coil spring 805 forming the other electrode of thevariable-capacitance capacitor forming the writing pressure detector 80Eand the circuit board 90E is necessary.

In the example of FIG. 12, only the terminal member 802 is placed on thewriting pressure detector placement part 93E of the circuit board 90Eand is electrically connected and fixed. However, an electrode piece orconductor pad pattern to be connected to the terminal piece 805 b of thecoil spring 805 may be formed on this writing pressure detectorplacement part 93E and the terminal piece 805 b of the coil spring 805may be electrically connected to the electrode piece or conductor padpattern by soldering or the like. In this case, at the line part 94E, aline pattern electrically connected to the electrode piece or conductorpad pattern connected to the terminal piece 805 b of the coil spring 805is formed in addition to the line pattern electrically connected to theterminal member 802.

Fourth Embodiment

The above embodiments are the cases of an electronic pen of theelectromagnetic induction system. However, this disclosure can beapplied also to an electronic pen of the active capacitive couplingsystem that indicates a position by transmitting a predetermined signalto a position detecting device by the capacitive coupling system.

Also in this electronic pen of the active capacitive coupling system,parts similar to those of the above-described electronic pen can be usedas constituent components. However, in the case of the electronic pen ofthe active capacitive coupling system, a core body 30F (see FIG. 13 tobe described later) composed of a material having electricalconductivity, for example, a metal, is used instead of the core body 30composed of a resin in the above-described first to third embodiments.Furthermore, it is assumed that the coil 41 wound around the ferritecore 42 forms a circuit for obtaining a charging current that charges anelectricity storage element by the electromagnetic induction system.Moreover, a signal transmitting circuit for supplying a signal to theelectrically-conductive core body 30F is disposed on the circuit board.In addition, a configuration of electrical connection for supplying asignal from the signal transmitting circuit of the circuit board to thecore body 30F is added. Therefore, in this fourth embodiment, acomponent for signal transmission is composed of the core body 30F andthe signal transmitting circuit.

An example of an electronic circuit formed on the circuit board of anelectronic pen 1F of the capacitive coupling system in this fourthembodiment will be described with reference to FIG. 13.

In FIG. 13, numeral 101 denotes an electric double-layer capacitor andnumeral 102 denotes a diode for rectification. Numeral 103 denotes avoltage conversion circuit and numeral 104 denotes an oscillationcircuit forming the signal transmitting circuit of this example. Asillustrated in FIG. 13, in this example, one end of the coil 41 isconnected to the anode of the diode 102 and the other end is grounded(GND). Furthermore, one end of the electric double-layer capacitor 101is connected to the cathode of the diode 102 and the other end isgrounded.

The core body (electrode core) 30F penetrates through a penetration hole43Fa of a core pipe member 43F of a ferrite core 42F around which thecoil 41 is wound and is physically joined (engaged) to, for example, thewriting pressure detector 80 forming a variable-capacitance capacitor80C. In addition, the electrode core 30F is electrically connected tothe oscillation circuit 104 of the circuit board through a connectionline 105. Therefore, a pressure (writing pressure) applied to theelectrode core 30F is transmitted to the writing pressure detector 80due to the above-described physical joining of the electrode core 30Fand the writing pressure detector 80 forming the variable-capacitancecapacitor 80C. In addition, a transmission signal from the oscillationcircuit 104 is transmitted from the electrode core 30F via theconnection line 105.

The oscillation circuit 104 generates a signal whose frequency changesaccording to the capacitance of the variable-capacitance capacitor 80Cof the writing pressure detector 80 and supplies the generated signal tothe electrode core 30F. The signal from the oscillation circuit 104 isradiated from the electrode core 30F as an electric field based on thesignal. The oscillation circuit 104 is formed of an LC oscillationcircuit using resonance by a coil and a capacitor, for example. In atablet that detects a coordinate position indicated by the electronicpen 1F of this embodiment, the writing pressure applied to the electrodecore 30F can be obtained based on the frequency of this signal.

The voltage conversion circuit 103 converts the voltage stored in theelectric double-layer capacitor 101 to a constant voltage and suppliesit as a power supply of the oscillation circuit 104. This voltageconversion circuit 103 may be buck-type one with which the constantvoltage becomes lower than the voltage across the electric double-layercapacitor 101 or may be boost-type one with which the constant voltagebecomes higher than the voltage across the electric double-layercapacitor 101. Furthermore, the voltage conversion circuit 103 may bebuck-boost-type one that operates as a buck circuit when the voltageacross the electric double-layer capacitor 101 is higher than theconstant voltage and operates as a boost circuit when the voltage acrossthe electric double-layer capacitor 101 is lower than the constantvoltage.

When the electronic pen 1F of this embodiment is mounted on a chargerthat is not illustrated, an induced electromotive force is generated inthe coil 41 due to an alternating magnetic field generated by thecharger and the electric double-layer capacitor 101 is charged throughthe diode 102.

When the electronic pen 1F of this embodiment normally operates (whencharge operation is not carried out), the potential of the coil 41becomes a fixed potential (in this example, ground potential (GND)) andthus the coil 41 acts as a shield electrode disposed around theelectrode core 30F. The fixed potential of the coil 41 when theelectronic pen 1F normally operates is not limited to the groundpotential and may be a positive potential of a power supply or be anintermediate potential between the positive potential of the powersupply and the ground potential.

In the above-described fourth embodiment, the electronic pen 1F convertsthe writing pressure detected by the writing pressure detector 80 to thefrequency and supplies it to electrode core 30F. However, the signalattribute to which the writing pressure is made to correspond is notlimited to the frequency and the writing pressure may be made tocorrespond to the phase of the signal, the number of times ofintermittence of the signal, or the like.

Other Embodiments or Modification Examples

The above-described embodiments are explained as the cases in which thisdisclosure is applied to the electronic pen main body with a cartridgeshape housed in the chassis of the electronic pen. However, it goeswithout saying that it is possible to employ not such an electronic penmain body but a configuration in which the signal transmitter, theholder, and the circuit board are directly housed in the chassis of theelectronic pen.

In the above-described embodiments, the writing pressure informationdetected by the writing pressure detector is sent out together with thesignal for position detection from the signal transmitter. However, awireless transmitter may be disposed on the circuit placement part ofthe circuit board and the configuration may be made in such a mannerthat the writing pressure information is transmitted to the positiondetecting device through this wireless transmitter separately from thesignal for position detection.

Furthermore, in the electronic pen of the capacitive coupling system inthe above-described fourth embodiment, a signal is sent out from thecore body. However, a configuration may be employed in which, forexample, a sleeve-shaped component that surrounds the core body isformed by a conductor separately from the core body and a signal is sentout to the position detecting device through the conductor or by usingboth the conductor and the core body.

Moreover, in the above-described embodiments, the circuit placement partof the circuit board is bonded and fixed to the circuit board placementbase part of the holder by a double-sided tape. However, it goes withoutsaying that the circuit placement part may be bonded and fixed not onlyby the double-sided tape but by applying an adhesive.

These and other changes can be made to the embodiments in light of theabove-detailed description. In general, in the following claims, theterms used should not be construed to limit the claims to the specificembodiments disclosed in the specification and the claims, but should beconstrued to include all possible embodiments along with the full scopeof equivalents to which such claims are entitled. Accordingly, theclaims are not limited by the disclosure.

DESCRIPTION OF REFERENCE SYMBOLS

-   -   1 Electronic pen,    -   2 Chassis,    -   3 Electronic pen main body,    -   30 Core body,    -   40 Signal transmitter,    -   41 Coil,    -   42 Ferrite core,    -   43 Core pipe member,    -   50 Holder,    -   51 Tubular part,    -   52 Circuit board placement base part,    -   60 Cartridge chassis component,    -   80 Writing pressure detector,    -   90 Circuit board,    -   91 Flexible substrate,    -   92 Circuit placement part,    -   93 Writing pressure detector placement part,    -   94 Line part

The invention claimed is:
 1. A replaceable component of an electronicpen, comprising: a writing pressure detector configured to detect apressure; and a circuit board comprising: a flexible substrate; acircuit placement part, one or more circuits coupled to the circuitplacement part; a writing pressure detector placement part, the writingpressure detector coupled to the writing pressure detector placementpart; a line part between the writing pressure detector placement partand the circuit placement part, a conductive line pattern formed at theline part that electrically couples the writing pressure detector withthe one or more circuits; and an extending part that extends from thewriting pressure detector placement part in a direction that is oppositethe line part and the circuit placement part.
 2. The replaceablecomponent according to claim 1, further comprising a holder that holdsthe writing pressure detector and the circuit board.
 3. The replaceablecomponent according to claim 2, wherein the holder includes a firstrecess that receives the writing pressure detector and a second recessthe circuit board.
 4. The replaceable component according to claim 2,wherein the circuit board is coupled to the holder by double-sided tape.5. The replaceable component according to claim 2, wherein alongitudinal length of the flexible substrate extends in a direction ofa longitudinal length of the holder.
 6. The replaceable componentaccording to claim 1, wherein the writing pressure detector is arrangedsuch that when the replaceable component is placed in the electronic penthe writing pressure detector is configured to receive pressure.
 7. Thereplaceable component according to claim 6, wherein the writing pressuredetector includes first and second electrodes and a dielectric betweenthe first and second electrodes, the writing pressure detector includinga contact area between the first electrode and the dielectric, whereinthe contact area is configured to change in response to pressure appliedto the core body and capacitance is varied according to the change inthe contact area, and wherein the second electrode is located on andcoupled to the writing pressure detector placement part of the circuitboard.
 8. The replaceable component according to claim 1, wherein awidth of the line part and a width of the extending part are less thanwidths of the writing pressure detector placement part and the circuitplacement part.
 9. The replaceable component according to claim 1,wherein the writing pressure detector placement part is at an angle thatis transverse with respect to the circuit placement part.
 10. Thereplaceable component according to claim 9, wherein a portion of theline part is bent to place the writing pressure detector placement partat the angle that is transverse with respect to the circuit placementpart.
 11. The replaceable component according to claim 1, wherein theextending part is at an angle that is transverse with respect to thewriting pressure detector placement part.
 12. The replaceable componentaccording to claim 1, wherein a first surface of the extending partincludes a plurality of line patterns, the extending part include aplurality of through vias, a second surface of the extending partincluding a plurality of conductive pads, the second surface beingopposite the first surface, the plurality of conductive pads beingelectrically coupled to the plurality of conductive line patterns,respectively, on the first surface of the extending part by theconductive through vias, respectively.
 13. A method comprising: forminga replaceable component of an electronic pen, the forming comprising:forming, in a longitudinal direction of a flexible substrate, a circuitplacement part, a writing pressure detector placement part, and anextending part that extends from the writing pressure detector placementpart in a direction that is opposite the circuit placement part; forminga conductor pattern for one or more circuits on the circuit placementpart; coupling a writing pressure detector to the writing pressuredetector placement part; and forming a conductive line part between thewriting pressure detector placement part and the circuit placement partthat couple the writing pressure detector placement part to the circuitplacement part.
 14. The method according to claim 13, further comprisingcoupling the flexible substrate to a holder.
 15. The method according toclaim 14, wherein when the flexible substrate is coupled to the holder,the writing pressure detector and the writing pressure detectorplacement part extend in a direction that is perpendicular to thecircuit placement part.
 16. The method according to claim 14, whereincoupling the flexible substrate to the holder comprises usingdouble-sided tape to couple the flexible substrate to the holder. 17.The method according to claim 14, wherein the flexible substrateincludes one or more sections having a reduced width relative to widthsof the writing pressure detector placement part and the circuitplacement part.
 18. The method according to claim 17, wherein the one ormore sections are a plurality of sections and include the extending partand the conductive line part.
 19. The method according to claim 17,further comprising forming a plurality of line patterns on a firstsurface of the extending part.
 20. The method according to claim 19,further comprising forming conductive through vias in the extending partand forming a plurality of conductive pads on a second surface of theextending part, the second surface being opposite the first surface, theplurality of conductive pads being electrically coupled to the pluralityof conductive line patterns, respectively, on the first surface of theextending part by the conductive through vias, respectively.